The Effect of Fiberglass Nets in the Protective Layer of Concrete on the Bearing Capacity of the Bendable Elements

Much attention is paid to improving the reliability and durability of reinforced concrete structures in our country and abroad. The existing experience in the use of reinforcing elements made of composite materials glued to the surface of reinforced concrete structures at the stage of their operation to increase the reliability and durability of reinforced concrete structures gives positive results. However, this method has significant drawbacks, including mechanical damages, destruction of the adhesive layer on contact with the concrete surface, which occurs for various reasons – aggressive environmental influences and other factors leading to detachment or complete destruction of the materials being glued. The authors propose a new way to increase the reliability and durability of reinforced concrete structures by using fiberglass nets with high strength and resistance to aggressive environments, eliminating the disadvantages of the above solutions. The essence of the proposed method is that at the stage of construction of the structure, fiberglass nets are laid on pallets and sides of the molds, which, after installing the steel reinforcement in the design position, turn out to be in a protective layer of concrete between the mold and the reinforcement cage. This method eliminates the disadvantages of the method with the sticker of composites, since fiberglass nets are located inside a reinforced concrete structure, do not have an adhesive layer, cannot peel off when cracks and concrete damage occur under the action of loads, and are also protected from the direct influence of the environment, which makes it possible to ensure their operability for a long period of operation. At present, regulatory documents have been developed for the use of fiberglass net as reinforcing elements, and standards have been issued that establish requirements for nets made of composite materials. However, there are currently no regulatory documents for the calculation of reinforced concrete structures with steel reinforcement and fiberglass nets in the protective layer of concrete. In the article, as an example, it is proposed to use two valid documents for the engineering calculation of the strength of the bendable element – SP 63.13330.2018 “Concrete and reinforced concrete structures. Basic provisions” and SP 295.1325800.2017 “Concrete structures reinforced with polymer composite reinforcement. Design rules”.

A.V. KURSHPEL, Candidate of Sciences (Engineering), (This email address is being protected from spambots. You need JavaScript enabled to view it.),
V.Kh. KURSHPEL, Candidate of Sciences (Engineering)

Ural Federal University named after the First President of Russia B.N. Yeltsin, Institute of Construction and Architecture (17, Mira Street, Yekaterinburg, 620002, Russian Federation)

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